Robinson R22 BETA accident near Chandler, Arizona, July 25, 1997
On July 25, 1997 at about 10:30 pm local time, a Robinson R22 BETA (helicopter), registered N4008D, was destroyed in an accident near Chandler, Arizona (Memorial airport). It was an instructional flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The CFI's failure to recognize and correct for a vortex ring state, and his improper use of the flight controls, which resulted in the loss of control and uncontrolled descent.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 25, 1997 · about 10:30 pm local time
- Place
- Chandler, Arizona · Memorial · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R22 BETA · all R22 BETAs on the register
- Registration
- N4008D · no longer on the register · serial 1456
- Damage
- Destroyed
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The CFI and private pilot were practicing maneuvers at the airport. The CFI stated that the helicopter was suddenly in a nose-low attitude with a high rate of descent. He said he tried to raise the collective to stop the descent rate with no apparent result. The student stated that he began a 30-degree banked turn to the left. He said the instructor felt the turn was 'too lazy' and he took control of the aircraft and proceeded to increase the bank angle to approximately 45 degrees. The aircraft then began to pitch nose down, the collective and cyclic began to shake and vibrate, which he said continued until impact. The student is a private pilot with both single engine land and rotorcraft helicopter ratings. He had approximately 76 hours of fixed wing time and 223 hours in rotorcraft.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; rotorcraft: helicopter
- Flight time: 1,033 hours in all; 471 in this make and model; 308 in the last 90 days; 126 in the last 30 days; 900 as pilot in command; 688 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 5,400 hours
- Last inspection: 100-hour inspection, July 21, 1997; 14 hours since
- Maximum gross weight: 1,370 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320 B2C (piston); 0 hours total
The flight
- Departed from: CHD AZ at 10:15 pm
- Flight plan: none
- Runway 30, 8,000 ft by 50 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 300° at 12 knots
- Visibility: 50 statute miles
- Sky: scat at 15,000 ft
- Temperature: 106°F (41°C), dew point 50°F (10°C)
- Altimeter: 29.00 inHg
- Observation at 10:45 pm from FFZ, 18 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.